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DMFTwDFT: An open-source code combining Dynamical Mean Field Theory with various Density Functional Theory packages

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 نشر من قبل Vijay Singh
 تاريخ النشر 2020
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Vijay Singh




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Dynamical Mean Field Theory (DMFT) is a successful method to compute the electronic structure of strongly correlated materials, especially when it is combined with density functional theory (DFT). Here, we present an open-source computational package (and a library) combining DMFT with various DFT codes interfaced through the Wannier90 package. The correlated subspace is expanded as a linear combination of Wannier functions introduced in the DMFT approach as local orbitals. In particular, we provide a library mode for computing the DMFT density matrix. This library can be linked and then internally called from any DFT package, assuming that a set of localized orbitals can be generated in the correlated subspace. The existence of this library allows developers of other DFT codes to interface with our package and achieve the charge-self-consistency within DFT+DMFT loops. To test and check our implementation, we computed the density of states and the band structure of well-known correlated materials, namely LaNiO3, SrVO3, and NiO. The obtained results are compared to those obtained from other DFT+DMFT implementations.



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